1. Field of the Invention
The present invention generally relates to pumps for oil wells and, more particularly, is concerned with a full flow tubing stationary valve pump apparatus.
2. Description of the Prior Art
Low gravity crude oil deposits are scattered throughout North America and other parts of the world. Large deposits can be found particularly in western portions of the United States and Canada. Deposits may be at depths ranging from the ground surface to 2,000 feet therebelow. Most of the deposits are high water drive. Commercial removal of heavy crude oil with very little gas and high water drive from shallow depths can be very expensive and difficult. Recovery of viscous low gravity oil, however, may well represent a large portion of the future energy needs of North America from fossil fuels.
The commercial recovery of viscous low gravity deposits with conventional API pumps in most cases are marginal at best. Many adverse economic, hydraulic and mechanical changes are involved when attempting to pump this type of fluid, such as (1) reduced price per barrel with increased lifting cost; (2) costly water separating at the surface; (3) poor pumping efficiency (less BPD); and (4) severe emulsion created by excessive turbulence and restricted flow through conventional API ball and seat type valving with high emulsion creation equating to high oil/water separation cost at the surface.
A technique to increase pump efficiency and to lower emulsion creation could make the production of low gravity crude commercially attractive. Consequently, a need remains for some means to recover viscous low gravity oil which is cost efficient and easier to accomplish than by current methods of crude oil extraction.